Correct option is A
The
least count of a Vernier depth gauge is typically
0.02 mm. The least count is the
smallest measurement that can be accurately read using the gauge. It is determined by the difference between one main scale division and one Vernier scale division. Most Vernier depth gauges follow the same principle as a standard Vernier caliper.
Least Count Formula:
Least Count = Value of one main scale division − Value of one Vernier scale division
For a common Vernier depth gauge:
· Main scale division = 1 mm
· Vernier scale has 50 divisions corresponding to 49 mm on the main scale.
Least Count = 1 mm/50 = 0.02 mm
It consists of the following parts:
· Base
· Graduating Beam
· Clamping Screws
· Fine adjustment mechanism
· Vernier Scale
The beam is graduated with the main scale in mm.
